Replay Value in Games

GameStatics - "It’s fairly common knowledge in the gaming world that the reason there’s so much focus now on multiplayer games, multiplayer modes, and other features that cut into single-player gaming experiences, is because of the used games market. See, it’s well known that the used game market is crippling the games industry something fierce. A vast majority of gamers buy their games used, and when that happens the original publishers and developers don’t see a dime of that sale—all that money is kept by the gamestop or wherever you bought it at..."
(GameStop, Industry, PC, PS3, Xbox 360)